The present invention relates to a compound, which can be produced by chemical synthesis and can simultaneously alkylating and cleaving a double-strand DNA, a method for alkylating DNA using compound thereof, a method for cleaving double-strand DNA, and a pharmaceutical composition using compound thereof.
Base sequence of total gene, our human xe2x80x9cblue print of lifexe2x80x9d is under elucidation by the human genome project without few years. The fact that the disease or the aging will occur, if this blue print is damaged or acquires the damage, is well known. As a result of progress in the human genome project, many diseases including cancer can be understood in the DNA level and the total medical science including diagnosis and prophylaxis may be changed revolutionarily. Further, a therapeutic method based on understanding in the DNA level of these diseases, namely development of pharmaceutical products targeting causal gene of disease and its product is highly expected, however mediatory studies for applying the fundamental studies to the clinical studies have only been just started. Anticancer agents used at present are antibiotics mainly selected by screening, and are originally not produced by microorganisms for the purpose of their cytotoxic action for cancer cells, and among them, almost no substances based on molecular biological knowledge of cancer are known. If expression of the intracellular specific gene can be freely controlled extracellularly, ultimate therapeutic method in the gene level can be achieved.
Recently, we have found that antibiotic duocarmycin constructed heterodimer with a molecule of the other species such as distamycin to achieve cooperatively molecular recognition of DNA, and effective alkylation of base sequence can be achieved as compared with the case of duocarmycin alone (Proc. Natl. Acad. Sci. USA 93, 14405, 1996). Based on the result of the discovery, pyrrole-imidazole polyamide is bound with the alkylation site of duocarmycin as a DNA recognition site and we have successfully synthesized the molecule which can selectively alkylating DNA at any base sequences (Japanese Patent Application No. Hei 10-260710). However, the compounds only binding with pyrrole-imidazole polyamide as the DNA recognition site in the alkylating moiety of duocarmycin can not only have insufficient alkylation activity but also alkylate only one strand base sequence.
We have examined alkylation reaction with these molecules and DNA using computer modeling such as molecular dynamics of these compounds in detail, and found that as a result of the insertion of the linker such as vinyl group into the location of the cylcopropane moiety (segment A), which was a reactive site of duocarmycin, an improved alkylation efficacy of DNA could be expected.
The present invention provides alkylating agent with improved efficiency of DNA alkylation. Further, we have found in the present study that the alkylating agent of the present invention showed dimer-like behavior as well as simultaneously alkylating and cleaving the double-strand DNA, and had an action as the artificial restriction enzyme for the specific base sequence.
Consequently, the present invention provides novel chemical species, which can simultaneously alkylating and cleaving the double-strand DNA. Further, the present invention provides a method for alkylating and cleaving DNA using chemical species thereof.
The present invention further provides anticancer agent using compound thereof.